Superheater.



'PATENTBD MAY 7, 1907.

H. L. VAN ZILE'.

SUPERHBATER.

APPLICATION FILED MAY 28. 1994.

M L i W! flv u wmnw by H R/ .1. f

M. m f;

INVENTOR 1 r L i? I ATTORNEY No. 852,640. PATE'NTED MAY 7; 1907.

H. L. VAN Z ILE.

SUPERHEA'IER. APPLIUATION FILED MAY 28. 1904.

2 SHBETS-SHEET 2.

WIITNESSE I INVENTOR V l w I BY ATTOR N EY v UNITED STATES PATENT OFFICE SUPERHE ATE R.

Specification of Letters Patent.

ren med a 7, 1907.

Application filed May 28,1904;-. Serial No. 210,159- 7 5" New York, have invented certain new and :useful Im rovements in Superheaters, of

which the ollowin is aspecification.

im-"My invention re ates to combined boilers and superheaters and method for operating to the same.

The object of my invention is to provide a .means for-maintaining a supply of pure water for the purpose of flooding the superheater, and a convenient means for flooding the suerheater with water and removing the water rom the superheater and returning it to the reservoir.

My invention consists in providing, in combination with a boiler and superheater, a reservoir referabl located at an elevation above be super eater, in maintaining connections between the reservoir and the superheater, and between the boiler and the super.- 'heater in such a way that the boiler may be shut ofl from the s'uperheater, and the-reservoir put in commumcation therewith'for the purpose of flooding the'superheater and main- 4 taini a water circulation therein, and such that t e steam pressure from the boiler may ,.-.be.used to expel the water from the superheater back into the reservoir.

- It consists furtherinproviding connections between the reservoir and the steam space of I r type of boiler to illustrate my invention. It will be obvious, however, that'many of its the boiler whereby'steam maybe made to from the boiler to the reservoir and conensetherein and thus maintain a supply of pure Water, and in other novel features and constructions to be hereinafter more fully pointed out and described.

. The economic advantages of' using su erheated steam for power purposes have ong been well known and many forms of superhea'ters have been devised. The heating surface of, a superheater to be effective must be so placed as to come in contact with high During the normal operation temperatures.

1 of the superheater the steam passing through .,'it absorbsSufficient heat to prevent injury to *the superheater resulting from these tempergtares. Then, however, steam is being raised in the boiler, or when, from any other ""ciiiise, there is no current'ofsteam assing through the superheater, the super eater, ooded with water, will soon become be rag idly destroyed by the intense it. To obviate this difh ident of the city, county, and State of culty numerous plans havebe'en devised, by means of which, at" such"tiines',' the superheater has been fiootled fwith vvater from the boiler. It is wellkiro'iv'n) 'however, that a residue accumulates in'the tyatei in the boiler and forms a scale upon the'boile'rtubes which is very objectionable, and this scale upon the superheater tubes, whichare'subjected to a higher degree of heat, and which, on account of their being filled only with steam during the normal use of the superheater, causes them to acquire a much higher tem erature than the regular tubesof theb oiler jw 'hich are in contact with water, and on thisaccount is all the more objectionabl'e'a'nd results in the ragid destruction of tlie 'siiperheatertubes.

- he formation of'jscale onsthe heating surfaces of superheaters is at present oneof the chic? objectionsto theirjusel 'In my present invention I have provided means-"by which the superheater is efficiently protected by pure water.

In "the drawings ccompa'nying 'a'rid' forming part of this sp cificati'onjFigure 1 repre? sents a front view' p'arjti'ally section'of 1a boiler and superheatei" eniboc lyiiig' the proferred form of m invention; Fig. 2-rep1 'esents a plan view the. samepartially'iii section; Fig. 3 representsf a side'elevation partially in section, and Fi .14 re resents an enlarged partial section t ou'g" a portion of the rear water-leg and superheaterf-hea der.

I have'chosen the ivelliknown water -tube features are applicable to other forms.

The referencecharacters are used in the same sense in all of the drawings and the specification.

Numeral 1 representsthe steam drum of the boiler.

2 and 3 represent, respectively, the'front and rear water-legs which are connected by theusual water-tubes 4.

5 represents the tubes forming surface ofthe superheater.

So far as many of thefeatures of my invention are concerned thesuperheatin siirface may be in any convenient'form. prefer,

the heating however, to have the superheating' fs'urface,

formed, as illustrated- -iiithe drawingsjof one or more rows of tubes 5 which replaceor so" plant one or more rovvs of ivaterstube's; fT e superheater tubes 5 passd'irectly through the front] and rear watenlegs, in-side ofhcillow stays or tubes 6 whic'h are made of'a'ppr'opriate size, preferably to permitthe super-heater tubes to pass-through themwithoutmaking contact.- The superheater tubes are expanded into the front and rear headers 7 and 8. The headers are provided with plu s orhand-hole plates 9 opposite the ends the superheater tubes and they give convenient access to the interior of the tubes for the purpose of cleaning or renewing the same. The.

end of the front header Z is connected to a branch 10, one end 11' of which leads to the pipe 12 communicating with the steam space of the boiler, while the other branch 13leads to the reservoir 14 locatedyoutside of the boiler and'preferably at an'elevation above the superheater. are provided with valves "15and 16, respectively. The endof the rear header is connected with the T 1'2, one branch oi which communicates with the pipe 18 leading to the steam main, andjs controlled by the valve 19, while the other branch is controlled. by the valve 20 and leads through the pipe 21 to -the water-reservoir 14. Between the valve 20 and the pipe 2 1 I prefer to employ 'a U tube or return-bend 22 for the purpose of forming a water-seal as'will be hereinafter explained. The upper part of the water.-

reservoi'rgl l is connected with the steamspace of the boiler by-means of: the pipe 23,

communication through which is controlled by the valve 24. 25-is'a safety valve on the drum 14'; 261's a water-ga e, 27 is a pressure relief-valve, and 28 isa low-off.

29 is a water-gage on thewater-seal orreturn-bend 22.

30 is'afpipe-leading from the steam space of the boiler to the main, "and communication' through this pipe is controlled by the valve 31: i

The operation. of my lnvention is as follows'i Assume that the boiler is cold and that water iron-:1. :1.

a fire is about to bestarted in the furnace; that'th'e valves 16 and 20 are closed; that the superheater is cur ty', and that the reservoir 14 is'aheut half fil ed with water, the amount of water being sufficient, however, to somewhat .mcre than fill the super-heater. Assume, also. that the valves15, 19 and 31 are closed, and. that the valve 24 is open. If, now,'the valves 16 and 20 are opened the reservoir 14 will run down aiperheater; and when a fire into and fill llig'tu I is started in the harness and the water in the tubes 4 of the boiler, and the tubes 5 of the 'superheater', become heated, two independent circulations will be started, one in the boiler and one in the. superheater. The valve 24, controlling communication throu h the pipe 23, being open, willinsure an equa ization of ressure'in the superheater and the boiler; l boiler circulation will be able to enter or minle with the water in the su rheater circuation. The, superheater wi l, in fact, oper- The branches 11 and 13 one of the water, however, of the through the return-bend 22'. .The gage will enable the operator to readily observe pressure has reachedth" reqmiea when all of the water has been withdrawn from the superheater. When this has occurred the valves 27 and 20 will be closed and the valve 19 op'enedto allow the'ste'arnito pass to the main through pi e 18. All of the steam will then pass from the steam s ace of the boilerthrough the pipe 12 and; t ough the supenheater to the main. The amount of water in the reservoir 14 will be indicated by the water-gage26, and by; opening the valve 24, steam W111 pass fro m t and relatively cool. supply of pure disthe proper amount of water in the reservoir 14 for flooding the superheater.

it is not necessary to use distilled water, as :a single charge will not ordinarily contain enough impurities to form anappreciable scale on the tubes of the superheater;

estean lspacc f of the boiler into the drum and condense therein, the drum bein outside of the boiler tilled water is thus added as required to keep I In filling the reservoir 14.for th'e'first time roo It is of course obvious that after the super heater has been flooded and steam raised the Water in the superheater could be drawnofl' and allowed to escape, and an'entire" new charge condensed from the boiler in the ree GIVOHU T 5. Inasmuch, however, as thisl would waste considerable; water and-heat and-require considerable time, and especially, in-

asmuch as it mightbe necessary to shut thevalve 19 and sto the flow of steam through the superheate'r efore 'a suflicient amount of distilled water had been accumulated, 'Ipr'e fer to return the water from the superheater to. the reservoir in the manner described."

- The safety valve 25 is provided on the res ervoir-14 for the contingency which might.

arise should the operatorneglect to open the valve 24 when the valves 15 and 19 are closed during the raising of steam, as in this case an excessive and destructlve pressure might be developed.

*When steam is shut off by means oi closing;

the valve l 'while'the fire is stillburni :m the furnace, the valves lfivand 20 shoul be again opened to allow the water from the reservoir to again flood the superheater. 1

If the yalve24 is opened it will notbeneeessary to close the valve 15, as the ressure upon the water inrthe reservoir wo d be-ex actly equal to the pressure in the pipe 12 water'circulation 1n said superheater. and

the. water c1rcula-.

leading from the boiler. If, however, the valve 24 is closed while the superheater is flooded, it will be preferable to also close the valve 15, so that the development of steam at a more rapid rate in the superheater system than in the boiler may not be able to force the water from the superheater up through the pipe 12 into the boiler. Furthermore, I prefer to so proportion the heating surfaces of the boiler and of the superheater, with respect to the amount of water contained in the boiler and in the superheater, respectively, that steam will be generated at a more rapid rate in theboiler than in the superheater when the latter is flooded.

It will thus be seen that I have provided a 7 rapid and convenient means for flooding the heating surfaces of the superheater with pure water, and with means for maintaining and replenishing the supply of pure water. It will also be seen that by this arrangement said superheater from said supply and returning the Waterfrom said superheater to said supply, without erniittingit to mingle With the water of the l o oiler.v I 5 2 The combination with a boiler; of a superheater, valved steam connections between the steamspace of the boiler and the' superheater, a water-reservoir exterior to the boiler and means for flooding said superheater from said reservoir andreturningwater from said superheater to said reservoir.

Thecombination with a boiler and a superheater, of connections between the steam spaceof the boiler and the superheater of a reservoir, and means for producing'a reservoir, independent of tion' in saidboiler. 1'

14. The combination with a' super-heater and valved inlet and .outlet steam connections therefor, of a water reservoir and valved connections between said reservoir and the inlet and outlet ends respectively of said super-heatenthe inlet and outlet ends of said super-heater being arrangedat different levels whereby the heating of said super-heater when flooded, will produce a water circulation in said super-heater and reservoir.

5. The combination with a boiler and a superheater, of a valved connection between the steam space of-the boiler and the inlet end of the super-heater, a valved connection between the outlet end of the super-heater and the steam main, a water reservoir located above the super-heater, valved connections between said reservoir and the inlet and outlet ends respectively of said superheater, one of said connections bein provided with a U-bend to form a water sea 6. The combination with a boiler and a super-heater, of a valved connection be tween the steam-space of the boiler and the inlet end of the super-heater, a valved connection between the outlet end of the superheater and the steam main, a water reservoir located above the super-heater, valved connections between said reservoir and the inlet and outlet ends respectively of said superheater, one of said connections beingprovided with a U-bend to form a 'water seal, and a valved steam connection between the steam space of said boiler andsaid reservolr.

7. In a combined boiler and s'uperheater, I

the combination with the front and rear water-legs and the water-tubes of'a watertube' boiler, of superheater tubes between rows of water-tubes extending through said water-legs and connected to headers outside of said water-legs, areservoir at an elevation above said super eater tubes, 'valved connections between s 'd headers and said. reservoir and valved ltcahfi connections between the steam space of said boiler and saidsu er-heater.

8. I a flooding device for superheaters, the combination with inclined superheater tubes, of headers connected, respectively,

to the upper and lower ends of the superheater tubes, a reservoir, valved connections between said reservoir and said headers, and

a U tube or water-seal in the connections connect ng the lower header with the reser- In testimony whereof, I have signed my name to this specification in the presence ofv 1 two subscribing witnesses.

, HARRY LEE VAN,,ZILE. Witnesses:

EL A LUOH, I ROGER H. LYON. 

